Palladium Monosilicide, PdSi

Palladium Monosilicide, PdSi, is obtained as brilliant bluish grey fragments on treating any Pd-Si alloy, containing above 60 per cent, of silicon, with dilute potash. The free silicon dissolves, leaving the silicide as residue. Density 7.31 at 15° C.

It is attacked when heated in chlorine or fluorine. In air it tarnishes at dull red heat. Cold nitric acid and aqua regia attack it; caustic alkalies slowly act upon it; whilst hydrochloric and sulphuric acids are without action.